Art of treating castings



Dec. 19, 1922.

W. Y. STROH ET AL.

ART OF TREATING CASTINGS.

3 SHEETS-SHEET I.

HLED DEC.30, I919.

Dec. 19,1922. 1,439,454. W. Y. STROH ET AL.

ART OF TREATING CASTINGS.

FILED DEC. 30. 1919. s SHEETS-SHEET 2.

WFIH'VNESS G3 M K 19:14 &i&

Dec. 19, 1922. 1,439,454. w. Y. smon ET AL.

ART OF TREATING CASTINGS.

FILED Me. 30. sets. a SHEETS-SHEE] a.

WITNESS Patented Dec. 19, 1925.

4 UNITED STATES,

p, 1,439,454 PATENT OFFICE.

WILLIAM Y. STROH, OF PITTSBURGH, AND JAMES THOMPSON, OF OAKMONT, PENNSYL- VANIA, ASSIGNOBS TO CATHERINE STRAYER, OF PITTSBURGH, PENNSYLVANIA ART OF TREATING CASTINGS.

Application ,flled December 30, 1918. Serial No. 848,386.

To all whom it may concern:

Be it known that we, WILLIAM Y. S'I'ROH and JAMES THOMPSON, both citizens of the Unitedbtates, and residin respectively, in Pittsburgh, Allegheny ounty, Pennsylvania, and ()akniont, Allegheny County, Pennsylvania, have invented a new and useful Improvement in the Art of Treating Castings. of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in Which- Figure 1 is aside elevation of one form of apparatus which may be used in carrying out our invention.

Figure 2 is a vertical section of the same.

F'i ure 3 is a face view of the hammers on a arger scale.

Figure 4 is a section onthe line IV-IV' of Figure 2. V

Figure 5 is a detail sectional view showin r the spring seats, and

Figure 6 is a diagrammatic view illustrab ing one arrangement of the hammer elements with respect to the casting.

Our invention has relation to the art of treating castings, and more articularly to 'a novel method of finishing t e same. The invention, while applicable to castings of various metals, is particularly useful in connection with castings having hardened surface portions which are difiicult to finish by ordinary machine methods, and which have hitherto been finished by grinding. This grindin o eration is not on y a rather slow and di cu t one, butis objectionable for this kind of castings owing to the fact that it removes parts of the surfaced hardened portions, leaving thesarne of une ual thickness over the surface of the casting which is finished.

These objections are overcome b our invention. In accordance with suc invention We cast a blank which is ap roximate- 1y of the desired contour and imensions, but which will necessaril have more or less surface irregularities ac to the inherent imperfections in all, casting methods. The cast blank is then subjected, either throughout its entire surface area, or only to such portions of such area as It is necessary or desirable to finish, to a series of hammer blows imparted in rapid succession,

Prior to receiving these blows the casting -is preferably heated to about the proper forging temperature for that class of metal and is sub ected to this hammering action while so heated. During the hammering action the casting is moved as may be necessary to bring the different portions of its surface to be treated to the action of the hammer elements; and the latter are provided with means "for positively limiting their maximum stroke in the strikin direction. In this manner the surface ing hammered is reduced to the desired contour, giving a highly finished surface. By proper manipulation of the casting and of the hammers, this work can be very accurately done. It is also possible to rovide the casting with a more or less highly polished surface by these operations.

Our invention, in addition to providing a smooth and more or less polished finished surface, is also advantageous in that the hammering action has a benefical effect upon the metal by way of toughening it and thereby provides a casting with a more or less toughened surface portion. Manifestly, our invention can be. carried out by the use of a great variety of apparatus. For the purpose of illustration, we have herein shown and described one form of apparatus j suitable for that purpose, said apparatus forming the subject matter of the co-pending application of Willian Y. Stroh, one of the a plicants herein, and George W. Klages, aerial No; 353,665, filed Jan. 24, 1920.

This apparatus will now be described.

In these drawings the numeral 2 desig hates a supporting frame or housing having a base portion which is preferably provided with guides 3 whereby it may be movably mounted upon a suitable support and also having an upright ortion 2 in which certain of, the movabe parts hereinafter described are mounted.

4 designates a shaft which is mounted in I tric levers,

'provided with a ably seated in a vertically movable slide box 11 mounted in wa s or guides 12 of thehousing portion 2. T is slide box may be moved by any suitable means, as by the links 13 connected to opposite ends thereof and also connected to the lever arms 14 of a rocker shaft 15, said shaft being provided at one end portion with an actuating lever 16 which may be held in different adjusted positions. by a bolt 17 arranged to work in a slot 18 of the holding member 19. It will be readily seen that by moving the lever 16 to different positions the slide box can be raised or owered; and as the rollers 10 carried in sa d Slide box form the fulcrums for the eccenthe adjustment of said slide box will vary the eflective stroke of the toes 8. These toes 8 are arranged to retract the hammer elements after each blow of the latter. These elements, designated at 20, are removably secured on the outer ends of the plungers 21 which are mounted for horizontal reciprocation in suitable guides 22 in the frame or housing. Said elements may take various forms according to the particular nature of the work to be performed. In the form shown they have a relatively limited contact portion 23 extending transversely thereof; and, preferably, these contact portions, as shown in Figure 3, are staggered or out of line with respect to each other. The said elements have ofi'set lateral edges so as to interfit with each other in the manner indicated in this figure, and thereby strike partially overlapping blows.

The striking impulse is imparted to each plunger by means of a spring 24 seated at one end against a shoulder 25 on the plunger and at the opposite end in a pocket 26 of a seating block 27. This block is slidably mounted in suitable ides 28 in the frame or housing; and eacii pocket is preferably follower 29 which is indeyi endently adjustable by means of a screw-30.

he said elements have ofi'set lateral edges a unit to correspondingly vary the compres- V sion of all the springs by any suitable means jutment such as that shown. Such meansconsist of a hand lever 31 secured to a transversely extending rock shaft 32 and having lever arms 33 at opposite ends which bear against the studs 34 on said block. Whn the lever 31 is actuated, the block can be moved forwardly against the action of the s rings, or can be a owed to move backwardly under the action of the sprin s. The desired ad- 18 maintaine by providing the lever members 33 with slots 34 having the lockin devica35. v

Eac of the plungers 21 is provided with the shoulder 36 for engagement with one of thetoes 8 whereby, under the action of the eccentric, said'plunger is retracted against the action of its spring: until the predetermined compression of the spring is reached,

the underside of the corresponding plunger.

The shaft 37 is provided with an actuating lever 39. When this lever is moved downwardly from its normal position, shown in Figure 1, the fingers 38 will engage the plungers to retract them. Any desired plunger or plungers may tracted, inoperative position by inserting a pin through one o r the holes 40, provided therefor, in the frame or housing and into enga ement with the registering hole 41 in the unger. 1

T e operation of the machine will be readil understood by the foregoing description t ereof. The shaft 4 being continuously rotated, the series of hammer elements will strike a rapid and continuous succession of blows. For the purpose described, it is desirable that means be provided whereby the maximum stroke of each hammer element 11 the striking direction is limited. For this urpose each of the plungers is provided with a shoulder 42 which, at the limit of the striking blow, contacts with a stop block 43 secured in the frame or housing. In this manner each striking blow is stop d at a predetermined maximum point so t v t the effect upon the casting being finished is to reduce its surface irregularities to the desired extent and revent hammer indentations in such surace. The casting to be finished is supported in any suitable manner with respect to the hammer-elements. It may, for instance, be supported on a lathe and revolved to the action of these elements; or it may be laced upon any other suitable support, the c aracter of which will depend upon the form of the casting and the-particular surface or surfaces thereof to be finished.

While we have shown the machine provided with four hammer elements, we desire it understood that we are not limited to this particular number, but that a greater or lesset number may be employed as may be desired. In some respects superior work ma be done with a single hammer element, a though this re uires more time.

As will be un erstood the operator in each case is required to manipulate'the castin and adjust the hammering apparatus witfi especial reference tothe character of the casting being treated: Such operators will,

then be locked in this re:

however, readily become skilled in this class of work, especially when working with standard forms of castings.

By throwing water upon the heated cast-' ing from time to time during the hammerin; operation, a very considerable degree of polishing may be imparted to the hammered surfaces. This water serves to remove smile in a manner well known in the art of rolling metal plates.

()ur invention provides a method of finishing castings which is peculiarly advantageous for the reasons hereinbefore stated.

We claim:

1. As an article of manufacture, a casting having a finished and polished surface produced directly upon the surface of the castin; solely by the action of a series of hafnmer blows substantially as described.

2. As an article of manufacture, a cast body of any desired shape having' its surface hammer finished and hammer polished, substantially as described. i

3. In the method of treating castings, the steps consisting in casting a blank to a proximately the desired shape, heating t e same to approximately a forging temperature, and then subjecting the surface or surfaces thereof to be finished to a succession of hammer blows by hammer elements whose contact faces are of relatively small areas, and limiting the maximum stroke of the hammer elements independently of the cash lug being treated, substantially as described.

4. In the method of treating castings, the steps conslsting in casting a blank to a proximately the desired shape, heatingt 10 same to approximately a forging temperature, then subjecting the surface or surfaces thereof to be finished to a succession of hammer blows by hammer elements, and limiting the maximum stroke of said elements independently of the casting being treated, substantially as described.

5. In the method of treating castings the steps consisting in subjecting a cast blank of approximately the desired shape to a succession of hammer blows,'and limiting the maximum strokes of the blow producing element or elements independently of the casting: being treated, substantially as described.

6. In themethod of treating castings, the steps consisting in casting a blank to approximately the desired shape, then subjecting the surface or surfaces thereof to be finished to a succession of hammer blows, and limiting the maximum strokes of the blow producing element or elements independently of the casting being treated to form a smooth polished surface, substantially as described.

7. In the method of treating castings, the steps consisting in casting a blank to approximately the desired shape, heating the same, then subjecting the portion of the surface to be finished to a succession of hammer blows, and limiting the maximum stroke of each blow producing elementindependently of the casting bein treated to definitely limit the enetration t ereOf, substantially as describe I In testimony whereof, we have hereunto set our hands.

,WILLIAM Y. STROH. JAMES THOMPSON.

Certificate of Correction.

It is hereby certified that in Letters Patent No. 1,439,454, granted December 19, 1922, upon the application of William Y. Str'oh, of Pitts nrgh, and James. Thompson, of Oakmont; Pennsylvania, assignors' to Catherine Strayer, of Pitts-. burgh, Pennsyl error appears in the line 45,.for the'wo s slide blbck 27 am: also be adjusted as; and that read with this correction therein that the same may case in the Patent Oflice.

Signed and sealed this 6th day of February, A. D.. 1923.

- KARL FENNING.

M OM Mw' r of Patents.

rinted specification uiring. correction as follows: tge 2, The said elements ave ofl'set leteral edges read The the said Letters Patent should he conform to the record of the vania, for an improvement in The Art of Treating Castin an 

